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Jobisdone [24]
3 years ago
14

Roy is twice as old as Joan, and in 3 years the sum of their ages will be 21 years. Find their present ages.

Mathematics
1 answer:
Lisa [10]3 years ago
8 0

Answer:

Roy is 10 years old at present and Joan is 5 years old at present

Step-by-step explanation:

Let

x----> Roy's age

y----> Joan's age

we know that

x=2y ----> equation A

(x+3)+(y+3)=21 ----> equation B

substitute equation A in equation B

(2y+3)+(y+3)=21

solve for y

3y+6=21

3y=21-6

3y=15

y=5 years

Find the value of x

x=2y  ----> x=2(5)=10 years

therefore

Roy is 10 years old at present

Joan is 5 years old at present

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2 right triangles have identical angle measures but different side lengths. The first triangle has side lengths of 6, 10, 8 and
lisabon 2012 [21]

Answer:

Dilation

Step-by-step explanation:

Given: The first triangle has side lengths of 6, 10, 8 and the second triangle has side lengths of 3, 5, 4 such that these two right triangles have identical angle measures but different side lengths.

To choose: the correct option

Dilation refers to a transformation when a figure is reduced or enlarged.

Each side of the large triangle is halved to get the small triangle.

So, Dilation transformation maps the large triangle onto the small triangle

3 0
2 years ago
A car dealership has SUVs and sedans in a ration of 5:9. How many sedans does the car dealership have if there are 140 SUVs
Elza [17]

To solve this, all you need to do is compare the ratio to the amount of SUVS there are.

5/9 (SUVs to sedans)

140/? (SUVs to sedans)

140 ÷ 5 = 28

9 x 28 = 252

140/252

There are 252 sedans in the car dealership! :D

8 0
3 years ago
Read 2 more answers
verify that 1,-1,-3 are the zeroes of the cubic polynomial x3+3x2-x-3 and check the relationship between zeroes and the coeffici
Vikentia [17]

Answer: yea its 123445

Step-by-step explanation:

6 0
3 years ago
Determine the equation of a circle with a center at (–4, 0) that passes through the point (–2, 1) by following the steps below.
GaryK [48]

Answer:

Radius length: √5

Standard Form (Equation): (x + 4)^2 + y^2 = 5

Step-by-step explanation:

First we will determine the radius;

Center: (-4, 0)

Point on Circumference: (-2, 1)

d = √(-2 - (-4))^2 + (1 - 0)^2 = √(2)^2 + (1)^2

= √4 + 1 = √5

Therefore the radius is of length √5

Now the equation of a circle is in the form ((x - h)^2 + (y - k)^2) = r^2. The center is in the form (h,k) and r is the radius. Given this our equation would be (x - (-4))^2 + (y - 0)^2 = (√5)^2, or [simplified] (x + 4)^2 + y^2 = 5.

6 0
2 years ago
Read 2 more answers
A meter is 3.37 inches more than a yard swimmer a swims 100 meters and swimmer b swims 100 yeards how many more feet did swimmer
olga_2 [115]
Swimmer a swims 100 meters, which is 100 1-meters, which is 100
(1 yards +3.37 inches) = 100 yards + 337 inches.

1 yard is 3 feet, so 100 yards are 300 feet.

100 in is 8.33 feet so
337 in is (337*8.33)/100=28.07 feet


Swimmer b swims 100 yards, which is 300 feet

Swimmer a swam 28.07 feet.


4 0
3 years ago
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